Researchers offer new insights on how gene activity drives development of cartilage; providing a unique molecular atlas of human skeletal development and defining a strategy for joint cartilage repair.
In a series of studies developing human cartilage cells gene activity was compared with several other cell types. First cartilage cells were compared to 4 other types of developing human cells: precursors to bone, muscle, tendon, and ligaments. As cartilage matured genes specific to cartilage became increasingly active while genes related to other cells types became repressed. Then these developing human cartilage cells were compared to equivalent cells from mice to find many broad similarities in gene activity.
Comparison of ordinary human cartilage cells and stem cell derived human cartilage cells were also carried out in detail taking into account for genetics, genetic regulation and function. The team demonstrated stem cell derived cartilage does not fully develop in petri dishes, rather it retains genetic hallmarks typical of fetal cartilage; when transplanted stem cell derived human cartilage at a particular stage of development into an arthritic rat the cartilage lost fetal hallmarks and fully matured regenerating critical superficial zone.
